Well, of course the various uncompressed transfer syntaxes are supported on all platforms, i.e. Implicit or Explicit VR Little Endian and Expicit VR Big Endian, as well as Deflated Explicit VR Little Endian. RLE encoding/decoding is also supported on all platforms, including Xamarin iOS and Android.
Bitmap is not a supported DICOM transfer syntax.
When you render the images for display, they are converted into an internal image format of the specific platform. On iOS, this is the CGImage whereas on Android it is Android.Graphics.Bitmap.
For JPEG and JPEG-2000 DICOM images, support on Xamarin iOS and Android is restricted to 8-bit greyscale and RGB mages, which of course is a severe limitation since many JPEG compressed DICOM images are 10-, 12- or 16-bit. Eventually we hope to be able to support these extended grayscale formats on Xamarin as well, but for now only fo-dicom on .NET Framework and Universal Windows Platform support these grayscale bit depths with JPEG.
Regards,
Anders @ Cureos